Conventionally, when a tooth is pulled out, a false tooth is positioned in place of the pulled-out tooth, or a dental bridge treatment, in which surrounding teeth are employed as pillars and a crown is positioned in place of the pulled-out tooth, is performed, thereby maintaining a patient's oral health.
However, this treatment causes problems in which false teeth or artificial teeth resulting from the bridge treatment are weak in chewing foods, exert a bad influence on surrounding teeth, and may even damage other teeth.
Accordingly, implant treatment has been recently introduced and is being widely administered, and is characterized in that an artificial tooth root is formed, and an artificial tooth, produced so as to appear highly similar to a real tooth, is coupled to the artificial tooth root, so that a patient obtains an effect of using the real tooth.
Such an implant treatment is one dental medical treatment for securely fastening an attachment, to which a false tooth (an artificial tooth) is coupled, to an alveolar bone, and is typically carried out according to the following procedures: an implant recess having female threads formed in an inner peripheral surface thereof, to which a fixture having male threads formed in an outer peripheral surface thereof is screwed, is formed for implantation of the fixture in an alveolar bone having no tooth, the fixture is screwed to the implant recess, an abutment having a joint coupled thereto, to which a false tooth (an artificial tooth) is secured, is engaged with female threads formed in the fixture, a neighboring gum is sutured, and a false tooth (an artificial tooth) is coupled to the top portion of the joint.
In the above implant treatment process, the fixture implanted in the alveolar bone serves as a tooth root, and the attachment including the abutment and the joint is a connection component for integrating the fixture with the false tooth (the artificial tooth).
That is, as described above, the fixture and the attachment constitute an implant structure for securely fixing the false tooth (the artificial tooth) at the correct position, and are preferably formed of a metal material such as, particularly, titanium, having superior physical/chemical strength.
Although a typical prosthetic appliance or a typical false tooth damages surrounding teeth or bones over time, a false tooth (an artificial tooth) fixed by an implant treatment performs the function of the original tooth and has the same shape as the original tooth, and does not decay, so the implanted false tooth can be semi-permanently used.
Korean Patent Registration No. 10-0925766 discloses an attachment for use in implant treatment, which is applied to a dental implant and is milled or prepped into a shape suitable for accepting a dental prosthetic, and in which a recess extends axially upwardly from an axial bottom end of a metallic appendage and is shaped to fit over an O-ball or an O-ring receiver abutment of a dental implant, an abutment including a coupling protrusion is provided, the coupling protrusion is repositioned in a coupling recess formed in an upper portion of a fixture, the abutment is fastened to the fixture using a screw, a prosthesis including a screw hole is provided, and dental cement is put between the abutment and the prosthesis to bond the prosthesis to the abutment.
In addition, Korean Patent Registration No. 10-1042372 discloses an integral-type implant, which includes a screw portion provided at a lower portion of the implant and having threads formed in the outer surface of the screw portion so as to be rotated about one axis and implanted into a dentary bone, and an abutment provided at an upper portion of the implant, the abutment being integrally formed with the screw portion and being capable of being embedded in a gum covering the dentary bone and of being covered with a cap. The abutment includes a gingival level portion, which is brought into contact with the gum, and a protrusion portion, which is provided at an upper portion of the gingival level portion and to which the cap is removably attached. The protrusion portion has a coupling recess extending downward from the top surface thereof in an axial direction, and the coupling recess has a sectional shape that may engage with a driver used to rotate the implant.
In addition, Korean Patent Publication No. 10-2007-0112075 discloses a separable-type abutment for a dental implant, which is fixed to a fixture implanted into an alveolar bone to support a dental prosthesis. The abutment includes a lower member fixed to the fixture, an upper member fixed to the dental prosthesis, and a coupling structure for removably coupling the upper member to the lower member.
However, the above-described conventional attachments have a problem in that a denture cannot be coupled to a denture-fixing attachment when several fixtures implanted into a patient are not arranged parallel to each other, thereby requiring another operation for implanting the fixtures parallel to each other or connection work using additional parts.
To solve this problem, Korean Utility Model Publication No. 20-2013-0005969 (entitled: DENTURE-FIXING ATTACHMENT FREELY ADJUSTABLE IN ANGLE AND POSITION) has been recently devised.
The attachment, as disclosed in the above document, is configured such that, when a denture is connected to a fixture implanted in a slanted direction, the denture can be connected to the fixture without additional parts, thereby enabling a doctor to comfortably and easily perform an implant treatment for a patient.